is the ozone regime, articulated in the 1985 Vienna Convention for the Protection of the Ozone Layer, the 1987 Montreal Protocol on Substances That Deplete the Ozone Layer, and the 1990 London Amendments to the protocol. This regime, in its current form, commits its members to phasing out the production and consumption of CFCs and a number of related chemicals by the year 2000. The regime represents the first concerted international effort to mitigate ''a global atmosphere problem before serious environmental impacts have been conclusively detected'' (Morrisette, 1989:794).

The political history of the ozone regime begins as a national issue in the United States and a handful of other Western countries in the early 1970s, in connection with emissions from supersonic transport (SST) aircraft and then from aerosol spray cans (Downing and Kates, 1982; Morrisette, 1989). Environmental groups organized opposition to the development of the SST and to the extensive use of aerosols. Individual responses led to a sharp drop in sales of aerosol products (Morrisette et al., 1990). The U.S. Congress, prodded by government studies supporting the CFC-ozone depletion theory and its links to skin cancer, approved the Toxic Substances Control Act of 1976, which among its other provisions, gave the Environmental Protection Agency (EPA) the authority to regulate CFCs. In 1978, the United States became the first country to ban the nonessential use of CFCs in aerosols. However, the EPA ruled that other uses of CFCs, such as in refrigeration, were both essential and lacked available substitutes.

Ozone depletion emerged as a major international issue in the 1980s. This occurred primarily as a result of initiatives by the United Nations Environment Programme (Morrisette, 1989) and the actions of the international scientific community (Haas, 1989), with the support of the international environmental movement. The Vienna convention of 1985 embodied an international consensus that ozone depletion was a serious environmental problem. However, there was no consensus on the specific steps that each nation should take.

A number of events in 1986 and 1987 created a new sense of urgency about the depletion of stratospheric ozone. These included a rapid growth in demand for CFCs due to new industrial applications and the end of a global economic recession; important new studies by the World Meteorological Organization, the National Aeronautics and Space Administration, the Environmental Protection Agency (EPA), and the United Nations Environment Programme; and, most important, the widely publicized